Rolling mill



J. M. PERRY.

ROLLING MILL. APPLICATION FILED NOV-14. I9 l7- RENEWED FEB. 11. 1922.

1,411,583. Patented Apr. 4, 1922.

Uhii'l'hi) STATES PAT JENT QFElCE.

JAMES M. PERRY, OF DETROIT, MICHIGAN, ASSIGNOR TO HIMSELF AND ALBERT B. HANSON, OF DETROIT, MICHIGAN.

ROLLING MILL.

Application filed November 14, 1917, Serial No. 201,910. Renewed February 17, 1922. Serial No. 537,357.

1 '0 all 1071 0771, it may concern:

Be it known that 1, JAMES M. PERRY, a citizen of the United States, residing at De troit, in the county of Wayne and Estate of Michigan, have invented a new and useful Improvement in Rolling Mills, of which improvement the following is a specification.

My invention relates to improvements in rolling mills, pertaining more particularly to mills of the three-high type.

Rolling mills of this general type generally operate in such manner that the plate/ is reduced in only one of the two passes, the lower pass being the active pass, the upper pass-the pass through which the return travel of the plate is had-being an inactive or dummy pass. This latter result is due to the fact that in commercial operation it is desirable that the intermediate roll operate in what may be termed a wedge-space, the introduction of the plate tending to move the intermediate roll in the direction of decrease of the space. To produce this effect, the intermediate roll axis is mounted slightly in advance or forward of the plane which extends through the axes of the upper and lower rolls (the term advance or forward being used with respect to the side of the mill from which the plate is introduced into th lower pass) hence when the plate is introduced into the lower pass the tendency is to move the intermediate roll farther along the periphery of the lower roll and thus in the direction of decrease of the wedge-space set up by the peripheries of the upper and lower rolls with respect to the periphery of the intermediate roll. When, however, the plate is introduced into the upper pass from the opposite side, the plate advance is in a direction to move the intermediate roll out of such wedge space, and hence there is no reducing pressure applied.

In an earlier patentNo. 1,159,581,'November 9, 1915-an attempt was made'to meet this condition and permit both passes to become active as reduction passes, this being obtained by mounting the upper and lower rolls with their respective axes on two spaced-apart and parallel vertical planes, with the axis of the lower roll on the plane which is forward under lower pass. operation, and the axis of the upper roll on the plane which. is forward in upper pass op- Specifieation of Letters Patent.

erations, the latter plane, of course, being th rear plane when operating under lower pass conditions. Vith this arrangement, the intermediat roll is shiftable to place its axis on either one or the other of such planes diate roll in the direction of decrease of the c wedge space. This same result is present when operating under upper pass conditions with the axis of the intermediate roll shifted to the plane of the axis of the upper roll, thus placing the axis of the intermediate roll forward of the connecting plane if considered with respect to the upper roll and rearward of such plane if considered in connection with the lower roll.

The structure just described, however, re-

quires that both the upper and the lower rolls be positively driven, and this brings in certain diilicultics through the ciliects on peripheral speeds, etc. and also requires manual shifting of the intermediate roll to locate its axis on the desired plane.

The present invention is designed to meet these objections through employing but the one positivelydriven or driving rollthis being the lowerlroll and at the same time produce the effect of tending to move the intermediate roll in the direction of decrease of the wedge-space whether the lower or upper pass is being utilized for reduction purposes.

This result is obtained by a relative arrangement of the rolls such that in operation th wedge space is maintained on the same side of the vertical plane of the axis of the lower roll, whether operating under upper or lower pass conditions, and in which the forces acting on the intermediate roll tend to move it in the direction of decrease in the wedg space. a

To these and other ends, therefore, the na ture ofwhich will be readily understood as the invention is hereinafter disclosed, said invention consists in the improved construction and combination. of parts hereinafter similar reference characters indicate similar parts in each of the views,

Figure 1 is a diagrammatic view of the three rolls of the mill of the present invention in position for lower passoperation.

Fig. 2 is a similar view showing the same rolls operating under upper 'passconditions.

Fig. 3 is an end "iew, partly in section, of the mill withthe rolls in the position of Fig. 1.

Fig. 4 is an enlarged view of portions of the upper and intermediate rolls in the position of Fig. 2.

In the present invention the three rolls are of conventional type, the lower roll being' represented at 1, the intermediate roll at 2, the upper roll at 3, these being mounted in housings A. The axes of rolls 1 and 2 are substantially fixed, while that of the upper roll 3 is shiftable within the limits permittedlby bearing block 5, the latter having a length less than the width of the housing space within which it is located, so that iii operation a space 4 will be provided at one or the other end of the block depending on which pass/is being used, as presently explained.

As'shownin Figs. 1 and 2, the axis of roll 1 is mounted on a vertical plane a, while the roll 3 is movable toward and from a vertical plane 12, the roll being located on such plane in the position of Fig. 1 and movable therefrom toward plane a when in the position of Fig. 2. As shown, planes or and b are spaced apart and extend parallel with each other.

Intermediate roll 2 has its axislocatcd between planes at and b and more particularly between plane a and the plane connecting the axes of rolls 1 and 3 in either position of roll 3, the two connecting planes thus produced being indicated as 0 and 0 respectively. If the side of plane a on which the plate is introduced to the lower pass be considered'as forward, the axis of intermediate roll 2 is located rearward or back of plane a and forward of either plane or c. The precise location of the axis of intermediate roll 2 relativeto plane a may vary. but,

in general, the distance between the axis of the roll and plane a approximates onefourth the distancebetween planes (1 and c. For purposes of illustration, Ihave shown the axes of rolls 1 and 2-connected by a line rl, and the axes of rolls 221ml 3 connected by two lines o and e, the former being the line connecting the axes when roll 3 is in the position of Fig. 1, line 0 being the line connecting these axes when roll 3 is shifted to the position of Fig. 2. 'Aswill be understood the tangents o the contacting surfaces of the several rolls will extend at right angles to lines d, e and 6 respectively, and these tangents would serve as the bounds of a wedge space which decreases in width in the direction of arrow B in Figs. 1. and 2. It will be understood, of course, that the rate of decrease in such width is less in Fig. 2 than in Fig. 1, since the tangents of Fig. 2 approach more closely a condition. of parallelism.

Referring to the disclosure of Fig. 1 in which a plate 6 is shown as-being introduced into the lower pass, the direction of rotation of the rolls is shown by the arrows. As will be seen the axis of roll 2 is shown to the right of plane a, and hence line (Z is to the right of the point of intersection of plane a and'the contacting arcs of rolls 1 and 2. Similarly,'the"axis of roll 3 is to the right of a vertical plane extending through the axis of roll 2-and line e intersects the contacting'arcs'of rolls2 and 3 to-the right of the point where such a vertical plane through the axis: of roll 2 would intersect such arcs. Consequently, the superposed rolls are each on the same side of the respective vertical planes extending through the axesof the rolls below, with the result that roll 3 will,under' the conditions'of Fig. 1, have its axis located on plane 6, moving to such plane from the position of Fig. 2 whenever the upper pass is not being used actively.

When plate 6 is introduced into the lower pass, the tendency of roll 2 is to move in the direction of arrow B, or teiid to follow the curvature of roll 1, the tendency being away from plane a, said plane intersecting the circumference ofroll 1 at its highest point. Since roll 2 is in contact with roll 3 and is itself drivenby the plate, roll 3 will also be driven, but since the axis of roll 3 is located on plane 6 at this time and is therefore considerably to the right of a plane extendin vertically to the'axis of roll 2--and whici plane would intersect the circumference of roll 2 at its highest pointthe rolling contact is inefieetive to shift the position'of the axis of roll 3, so that the wedge-space produced by the tangents of rolls 1 and 3 will remain substantially constant, the upward 115 movement of roll 2'in presence of the late not afl'ecting this result, roll 3 maintalning its position shown in Fig. 3.

In Fig. 2' the rolls are in theposition produced by the introduction of a plate 6 120 into the upper pass. Since reduction in plate thickness tends tobuild up a relative bank on the-plate at the" entrance to the pass, the advance of theplate through totation of roll 2 shifts'the position of roll 3 from the dotted line position in Fig. 2---the position of the roll in Figs 1 and 3-to the full line" position. thus shifting the connect ing plane from the position show-nut cto that shown at c, the shifting length being limited by contact of block 5 with the housing-the opposite position of block 5 from that shown in Fig. 3.

While this shift in roll 3 has provided a shift from line 6 to the position on line 6, the effect is not changed since line 2' also intersects the contacting arcs of rolls 2 and 3 to the right of a vertical plane through the axis of roll 2, and since roll 2 is not only held by its mounting from shift in the same direction, but, in addition, the point of contact of rolls 1 and 2 is to the right of plane a'-and would therefore require that roll 2 move in an upward direction to cross plane a.there is produced a tendency of the roll 2 to move in the general direction of arrow B in Fig. 2, viz: toward the right and in the direction of rotation of roll 1 or in the direction to tend to bring the axis of roll 2 toward the line 0, thus preserving the effectiveness of the upper pass by tending to move the intermediate roll in the direction of decreasing width of the wedge space be tween rolls 1 and 3, as in the forward pass.

As will be understood, roll 3 tends to mount roll 2 under the conditions of Fig. 2, due to the effect of the plate (3 in contact with the roll, but it cannot reach the point where its axis would pass a vertical plane extending through the axis of roll 2, due to the fact that space i is not sufficient to permit the travel necessary to reach such point. Consequently the strain lines 0 and 0 remain in rear of the axis of roll 2. And while the axis of the wedge space is shifted by this movement of roll 3, the shifting distance of the space axis is insullicient to de stroy the wedging action when operating under upper pass conditions, the rolls being maintained so as to preserve a wedge space with either pass operative and with the intermediate roll tendin to move in the direction of decrease of wedge width under either condition.

From the above it will be understood that the intermediate roll is reinforced or stabilized in both pass operations. Under lower pass conditions, this is provided by roll 8 which, through the downward pressure on roll 2 applied to the right of the vertical plane passing through the axis of roll 2, tends to crowd roll 2 toward the left and away from line 0, the plate 6 tending to prevent roll 2 from being crowded toward plane a by the action of roll 3. And while the absence of )late 6 in Fig. 2 eliminates this restraint, t e bodily movement of roll 3 to the position of Fig. 2, and the efieet of plate 6 in tending to retard the motion of roll 2 at the upper side and produce the frictional contact with roll 1 on the lower side, tends to prevent the movement of roll 2 in the direction of mounting roll 1 to plane a. So that the tendency of roll 2 is away from plane a in each pass operation,

although the location of roll 3 would seemingly tend to move roll 2 toward such plane a in both passes.

Having thus described my invention, what I claim as new is:

1. In a plate mill oi the three-high type and wherein the lower roll is the driving roll, means for supporting the rolls in a manner to locate the axes of the upper and intermediate rolls in rear of a vertical plane extending through the driving roll axis and with the axis of the intermediate roll forward relative to the strain line of the rolls.

2. In. a plate mill of the three-high type and wherein the lower roll is the driving roll, means for supporting the rolls in a manner to locate the axes of the upper and intermediate rolls in rear of a vertical plane extending through the driving roll axis, the axis of the intermediate roll being located permanently between such plane and the strain line connecting the upper and lower rolls.

3. A mill in claim 2 characterized in that the axis of the upper roll is shiftable perpendicular to such plane to vary the position of the strain line.

4. A mill as in claim 2 characterized in that the axis of the upper roll is shiftable in directions perpendicular to such plane to vary the distance between such strain line and the intermediate roll axis.

In a plate mill of the three-high type and wherein the lower roll is the driver, means for supporting said rolls in a manner to locate the intermediate roll within a wedge space in which wedging activity is produced, when the rolls are operating under lower pass conditions, the upper roll being shiftable to shift the axis of such wedge space distance insufiicient to destroy the wedging action when the rolls are operating under upper pass conditions.

6. In a plate mill of the three high type and wherein the lower roll is the driver, means for supporting the rolls in a manner to produce a wedge space by the relative locations of the upper and lower rolls rela tive to a vertical plane through the mill, the axis of the intermediate roll being positioned. to locate the intermediate roll within such space, the upper roll being shiftable relatively to such plane to shift the axis of the space, the shifting movement of the roll being insufiicient in length to destroy the wedging activity.

7. In a plate mill of the three-high type, and wherein the lower roll is the driver, means for supporting the rolls in a manner to maintain the axes of the lower and intermediate rolls substantially constant in position and permit shifting of the axis of the upper roll between two positions relative to vertical plane through the mill, the relative positions of the axes being such as to locate theintermediate roll within a wedge space in which wealging activity is produced when the rolls are operating under lower pass conditions, the shifting of the up er roll producing shift of the axis of the we( ge spacewith the distance of shift insufficient to destroy the wedging activity when operating under upper pass conditions.

8. A. mill of the type of claim 5 characterized in that the upper roll is, shiftable between two extremes of movement relative to a vertical plane extending through the axis of the lower roll with the extremes 0n the same side of such plane.

9. A mill ofthe type of claim characscribing witnesses.

JAMES M. PERRY. In the presence 0f- MICHAEL J. BAUER, JOSEPH KNAUBER. 

